Antibiotic associated nephropathy

Renal biopsies of 43 patients who developed renal complications after treatment with antibiotics were studied. The treatment with antibiotics in these cases was used for many different reasons such as: bronchitis, bronchopneumonia, cystitis, tonsillitis, sepsis, peritonitis, gangrene of the foot and tuberculosis. The renal function of these patients, before the treatment with antibiotics was normal. The biopsies were studied by light, electron and immunofluorescence microscopy. In 43 cases treated with antibiotics renal changes were shown. Three types of morphologic changes were found: acute tubular necrosis (ATN) (13 cases), acute tubulo-interstitial diseases (ATID) (21 cases), focal glomerulonephritis with crescents (FGN) (9 cases). The renal pathologic changes were most commonly seen in patients treated with 2 groups of antibiotics: aminoglycosides (21 cases) and antibiotics of the penicillin group (15 cases). The most characteristic feature of aminoglycosides is their direct toxic effect leading to ATN. Antibiotics of the penicillin type more commonly caused an allergic reaction leading to ATID (secondary to cellular mechanisms) or FGN (secondary to a predominantly humoral mechanism). Renal changes in the use of other antibiotics were much less manifest and were usually due to a hypersensitivity reaction. Cephalosporins, if used in combination with other antibiotics can increase their nephrotoxicity.